This application claims priority of UK patent application No. 0126344.1, filed Nov. 2, 2001, and UK patent application No. 0129379.5, filed Aug. 20, 2002.
Not Applicable
Not Applicable
1. Field of the Invention
The present invention relates to an improved sand for use in block paving applications, clay paviors, slabs and any other products in relation to the laying of paths, driveways, forecourts, patios and the like, or to any similar application where stability is required. Embodiments of the invention may also find utility for filling gaps between sections of runways and in various other heavy duty civil engineering applications.
2. General Background of the Invention
When laying block paving, for example as part of a road or driveway, it is known to fill the gaps between adjacent blocks with kiln dried sand so as to provide structural stability to the blocks. However, ordinary kiln dried sand has the disadvantage that it tends to disperse and disappear from between the blocks, especially during wet and windy weather or when the road or driveway is being swept, leaving gaps between the blocks. These gaps eventually result in structural instability, since the blocks then become free to move with respect to each other. Furthermore, the block paved road or driveway becomes unsightly, and weeds may grow in the gaps between the blocks. Indeed, ordinary kiln dried sand allows weeds to grow between the blocks even when the gaps are filled with the sand.
It is known to provide a polymeric sealant to block paved roads or driveways after laying, which can help to ameliorate these problems, but the application of sealant is time consuming and expensive.
It is also known, for example from U.S. Pat. No. 5,244,304, JP2285103 and JP 10265251, to provide a cementitious material including a polymer component for use in laying paving slabs and the like. These cementitious materials may be used as a base layer or as a jointing compound, but are disadvantageous in that once set, it is extremely difficult to clean up spillages and splashes which can cause staining of the paving slabs and the like. This is because cementitious materials tend to set permanently and cannot thereafter be removed without chipping or other physical force. These materials are also messy and unpleasant to apply, being in a paste-like cementitious form that is wholly unsuited as a jointing compound for block paving and the like.
Other jointing compounds known, for example, from DE 4421970, WO 00/50355 and WO 97/07303, use mixtures of liquid polybutadiene, a flow enhancer and dry particulate material such as sand, crushed glass or fine aggregate. These mixtures are advantageous in that they are relatively easy to handle and do not adhere to paving slabs or the like when spilled thereon. However, the mixtures are designed to set upon exposure to air or oxygen, which can make handling difficult and means that the mixtures require careful storage. Furthermore, flow enhancers generally contain environmentally-unfriendly organic solvents. It will be appreciated that polybutadiene is not a water-soluble polymer.
Finally, a coloured asphaltic paving material is known from JP 61254701. This material comprises a resin emulsion, quartz sand pigment, silica asphalt emulsion, a thickening agent and a defoaming agent. This material is used in a manner similar to ordinary asphalt, being spread in fluid form onto a surface (e.g. a tennis court) and allowed to set. It is wholly unsuitable for use as a jointing compound for block paving, being messy to apply and requiring heating.
According to a first aspect of the present invention, there is provided a non-cementitious, non-asphaltic material for filling gaps between paving blocks or the like, the material comprising dried sand or silicates mixed with a water-soluble polymer.
According to a second aspect of the present invention, there is provided a method of stabilising paving blocks or the like comprising a plurality of blocks laid adjacent to each other with gaps therebetween, wherein the gaps are filled with a non-cementitious, non-asphaltic material comprising dried sand or silicates mixed with a water-soluble polymer, and wherein water is applied to the material near upper surfaces of the blocks.
According to a third aspect of the present invention, there is provided a material for filling gaps between paving blocks or the like, each 106.5 kg of the material comprising: 100 kg kiln dried sand; 5 kg powdered vinyl acetate/versatate copolymer with kaolin filler and polyvinyl alcohol colloid protector; 0.5 kg herbicide/fungicide and 1 kg crystalline sodium silicate.
There are no drawings submitted.